We've been talking about Feed Useage and Residual Error in the past couple of threads.  Specifically why some stocks numbers have been so far off from expected values.

I've been throwing data around on Q1 F&R and 07 keeps popping up like production was over estimated.  So I went back and looked at the other quarters to see if Q1 07 was an outlier..  It wasn't. 

Here's the data from this source: http://www.ers.usda.gov/datafiles/Feed_Grains_Yearbook_Tables/US_Supply_and_Disappearance/FGYearbookTable04Full.pdf

I'm sticking with data since 2006 since this is the "modern ethanol era" where DDG's could be expected to impact feed useage (and presumably residual error.)   In 2006/07 etoh grind was 2,117 myn bushels ramping up to today's 5,000 expected grind.

As you can see the Q1 F&R mean is 2,118 with a standard deviation of 203 myn bushels.. so the mean minus one standard deviation would be 1,915 whereas the mean plus one standard deviation would be 2,321 (right or wrong I included 2013's 2,426 number...??)

Scott Irwin said that their work found stocks numbers flipping back and forth verses trader expectations.  I don't have the traders expectations but the data did not flip back and forth in 07.. nor any other year from a statistical reference of one standard deviation.

As you can see 07 and 13's Q1 F&R are greater than 1 Standard deviation above expected (bold in red) values.  Whereas, 2011's Q1 F&R is Below expected (bold in blue) values.  You can read the rest of the Chart..

2007 did not flip back and forth as Q2 was ALSO above one standard deviation as was the yearly value.  This makes me really question the 150.7 yield...  ???

From this analysis.. that Feed and Residual values outside of expected norms could indicate an over or under estimation of the crop.. there is evidence that both 2011 and 2012 crops could have been underestimated.

However, it will be interesting to see if the next stocks reports confirm the suggestion that the 2013 crop was overestimated by the record LARGE Q1 F&R bounding 1.5 standard deviations outside of expected values.

fwiw.

This is quick and dirty analysis and I could be wrong.  It would be interesting to get someone else take on this..

edit add:  My other hypothesis is that YIELD is not compensated for acreage.. aka as Harvested acres (in this table) expands.. there should be a YIELD PENALTY as more marginal acres and Corn on Corn acres are added.. vice versa there should also be a Yield BOOST as we fall back to the more core acres..

I believe the data shows this as 2009's record yield was on 79 myn harvested acres.  Whereas 2007 and 2013's acres were 7 and 8 myn acres above that..

Question:  Are THOSE acres going to yield as much as the Core acres?

I don't think they will.. all things equal.. and recognize that no two weather years are alike.